Earthmoving vehicles, such as track-type tractors, utilize various types of guards to protect vulnerable portions of the vehicle. One particular type of guard is a bottom guard which is secured to the bottom of an earthmoving vehicle to protect portions of the engine, transmissions, or other vital vehicle components. This type of guard is generally bolted directly to frame members of the vehicle, or to drilled and tapped blocks which are welded to the frame members. The bolts are generally aligned vertically and, due to flexure of the frame members during vehicle operation, the bolts are loaded in shear. This frame flexure, and movement of the guard during vehicle work operations, tends to loosen the bolts. If the bolts are not re-tightened, the guards may come completely detached from the vehicle, thereby exposing vital components to possible damage. Shear loading of the bolts can also occur when the guards hit or slide over objects, such as rocks or stumps. This sliding action produces wear of the bolt leads, making removal of the bolts difficult.
One type of bottom guard arrangement for a vehicle is shown in U.S. Pat. No. 3,993,153, issued Nov. 23, 1976, to David D. Hansen et al. The guard arrangement described in this patent includes front and rear guard members bolted to the vehicle frame and an intermediate guard member supported in a notch by the front guard and bolted to the rear guard. A plurality of shear blocks are welded to the front and rear guard members and any lateral or longitudinal applied to the intermediate guard are absorbed by the shear blocks rather than being applied to the bolts. Although this guard arrangement would appear to prevent shear loading of the bolts which secure the intermediate guard, it is a rather bulky and complicated arrangement requiring a considerable number of parts.
Another type of guard and connector assembly is shown in U.S. Pat. No. 3,874,624, issued Apr. 1, 1975, to Albert Gianessi. The belly-type engine guard described in this patent is held in place by a connector assembly to the main frame of the vehicle. The connector assembly includes a plurality of brackets welded to the vehicle frame and a plurality of connector nuts adapted to mate with portions of the brackets. Threaded bolts penetrate the guard and mat with the connector nuts to hold the guard in place. Additionally, the connector assembly includes a plurality of shear blocks welded to the vehicle frame and mating tapered openings in the guard and reinforcing blocks welded to the guard. The shear blocks are intended to transfer relatively large horizontal forces exerted on the guard directly to the frame members to avoid shearing of the threaded bolts. As with the above previously described patent, this connector assembly relies on shear blocks to relieve the bolts of the shear forces. The heads of the threaded bolts of this connector assembly are exposed to wear and will prevent easy removal of the bolts.
The present invention is directed to overcoming one or more of the problems as set forth above.